A wide variety of display devices have been designed and manufactured for use in merchandising shelved products to consumers. There are several major disadvantages of prior racks with adjustable shelving. In some of such prior racks, the act of adjusting of the shelves is a complicated manipulation of multiple rack and/or shelf parts; this may result in erroneous shelf adjustment causing the shelves to be insufficiently stable. In some other prior rack arrangements, shelf adjustment may require deformation of shelf and/or rack parts by application of a significant force which may necessitate involvement of multiple people; this creates an undesirable inefficiency and inflexibility in using such racks.
In short, there is a need for a display rack having an adjustable shelf or shelves which can be horizontal or inclined as desired to optimally display one or more item, which is exceptionally simple, economical and sturdy, and in which the shelf or shelves are comparatively-easily lockable into the desired position.